Sewing-machine.



K. A. STRITTER. SEWING MACHINE.

APPLICATION FILED DEC. 30, 1914.

Patented Jan. 16, 1917.

Imam {S 1 ITED STATES PATENT OFFICE.

KARLA. s'rnrr'rnn, 0F NAHANT, MASSACHUSETTS.

SEWING MACHINE.

Specification of Letters Patent.

Application filed December 30, 1914. Serial No. 879,ti42.

To all whom it may concern:

Be it known that I, KARL A. S'rRIT'rER, a citizen of the United States, residing at Nahant, in the county of Essex and State of Massachusetts, have invented certain new and useful Improvements in Sewing- Machines, of which the following is a speci fication.

My invention relates to sole sewing machines and it has for its object to provide an improved machine of this kind that is particularly adapted to be used to sew the bottom welt strip to the tread, side of the sole of the improved rubber-soled boot or shoe shown and described in my appllca tion for Letters Patent of the United States filed December 8, 1914, Serial No. 876053.

The present invention consists, broadly, of a sole sewing mechine having means for directing a welt strip into position onto the tread side of the sole of a boot or shoe and into the path of the needle so that said welt strip receives the sole attaching stitches and is sewed to the tread side of the sole at the same time that the sole is sewed to the upper part of the shoe.

In the preferred form of my invention the prcsser foot of the sole-sewing machine is constructed to serve also as a welt-strip guide by means of which the tread welt strip or the like is guided into position on the margin on the sole and into the stitching lincas the operation of sewing the sole progresses, the said presser-foot guide serving, together with the n'lanipulation of the shoe by the operator, to bend the tread welt sidcwise without buckling as the sewing proctwds around the bends or curves, particularly while traveling around the toe.

Other features of my invention are hereinafter pointed out. V

In the accompanying drawings-Figure 1 is a front elevation of a sole sewing machine embodying one form of my invention. Fig. 2 is a front elevation of the presser foot of the sewing machine shown in Fig. 1. Fig. 3 is a side view of the pticsser-foot. Fig. 4- is a top plan View of t I presserfoot. Fig. 5 is a bottom plan view of the 'n'cssor-loot. Fig. (5 is a detail partly in section. Fig. 7 is a detail described later.

Fig. 8 shows a modification.

llcrcln T have shown my invention as embodied in a machine for sewlng soles to -of the recess f.

welts but, as will be clear later, the invention may be embodied in other sewing machines.

' Having reference to the drawings; A represents the work rest or table, B the awl,.

the aw]. On its under face the presser foot is made with a longitudinal recess f bordered upon its rear side by a relatively deep longitudipal shoulder f and upon its front side by a relatively shallow.longitudinal shoulder f Adjacent the inner end of slot f and upon the under side of the pre siser foot is a guide fin or boss i located about Patented Jan. 16, .1917. i

types of sole midway between the shoulders f and f At its advance end the presser foot is made with an upwardly oblique guide tube or passage f whose lower end 15 at one end The presser foot just described is for Use with a welt strip G made as shown in Fig.

7 and the end of said strip is threaded down through the passage f with its lower end occupying the recess 7 and held in the paths of the needle and awl by the shoulders 7" and f. The top side of welt strip G may be formed as shown with a longitudinal groove 9 the purpose of which will presently appear. lVhen the welt strip is threaded down through the presser foot the fin f" occupies the groove 9 and thereby assists the shoulders f and f in holding the strip against lateral displacement thus insuring its proper presentation to the needle and awl.

When the machine is in operation sewwelt G is held against buckling or rising under the thrust of the awl by the arms or tines f and f at each sideof the awl The sole H may be made upon its tread side with a marginal recess 9' within which the stripv G is laid by the welt guiding presser foot F whose up and down movements combined with the feed ofthe work serve to force or crowd the welt strip accurately and \fully into the recess 9; This is important and desirable particularly where the welt -strip G and its recess 9 are treated withfcement before the strip is applied to the sole. It is desirable to make the arms or tines f and f at least as long as the distance between two stitches produced under the maximum feed stroke of the awl sothat each time the presser foot descends onto the work for a new stitch the two arms or tines not only hold the welt strip G down onto the sole at each side of the awl while the latter is passing through the work but also at the same time press and hold down the material of strip G at each side of the preceding stitch, thereby maintaining intimate contact at that point and practically subjecting all parts of the strip G to pressure from the presser foot for a period of time equal at least to the time required to make two stitches.

In sewing around sharp inward turns as,

for example, the toe the welt strip G tends to draw out sidewise from under the presser foot as it leaves the latter and ordinarily the shoulder f will oppose this and serve to hold the strip against displacement relactively'to the needle anda'wt while making such turns, but the engagement of the fin f with the groove 9 of welt G further insures against displacement of the welt strip relatively to the needle and awl and also causes the stitches to follow and occupy the groove.

In making an out turn as when sewing from the shank to the ball of the sole, the shoulder f9, assistel bv fin f maintains the welt strip in proper position relatively to thef needle and awl.

The form oflpresser foot Shiown F g. 8.. a

is intended for stiff and comparatively heavy welt strips G cut from full grain leather and is characterized by having its recess 7 and passage f curved in the same direction as an lnward turn on the sole'as at the toe. This curved shape of the presser foot acts to impart a curved shapeto the welt strip as it is delivered to the-needle and awl and materially assists in properly'negotiating sharp inward turns.

In order that .the welt strip G will be deliver-ed onto the sole H in an exact and definite position relatively to the work table or rest A so that it will properly fit into the recess 9, the work rest by which the shoe is guided during the sewing operation, should be accurately positioned relatively to reincluding a guide tube leading toward the needle and a projection on the work-engaging face of the presser foot located wholly and immediately between the delivery end of said tube mu said needle for engaging the groove of the \velt'strip to guide the latter into the path of the needle as it leaves said tube so that said welt strip receives-the.

sole attaching stitches and is sewed to the solo at the same time that the sole is sewed to'the'upper portion of the shoe.

n In testimony whereof I have afiixed my signature,.in presence of two witnesses. V

. KARL A. STRITTER.

' \Vitnesses:

' ERNEST A TELFER, EDWIN T. LUCE. 

